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concentration of oxygen

...seasons, especially when vertical mixing is greatly enhanced because of a lack of thermal structure and increased wind stirring, lakes are replenished with oxygen. In the warmer seasons, although surface waters may remain more or less saturated and even supersaturated, the concentrations are lower. Beneath the surface, oxygen consumption through biological decay may cause serious depletion....

heat transfer

When a lake is stratified, the most important process for downward transfer of heat to the hypolimnion is through eddy conduction. The coefficient of eddy conductivity is determined empirically and varies substantially from lake to lake. Mixing processes are generally more active in coastal areas, so that isotherms can be expected to slope downward toward shore. In large, relatively unprotected...